Accession Number:

ADA289579

Title:

An Optoelectronic Attenuator for the High-Speed Control of Microwave Integrated Circuits.

Descriptive Note:

Final rept. Nov 90-Dec 93,

Corporate Author:

ARMY RESEARCH LAB ADELPHI MD

Personal Author(s):

• Saddow, Stephen E.
• Lee, Chi H.

Report Date:

1994-11-01

Pagination or Media Count:

83.0

Abstract:

An optoelectronic attenuator suitable for the optical control of microwave integrated circuits is presented. High-speed photoconductive switches are embedded in planar microwave transmission lines, and semiconductor laser diodes LDs are used to control the microwave signal level on these high-speed lines. With a silicon coplanar waveguide-photoconductive switch SiCPW-PCS, up to 45 dB of microwave attenuation has been achieved with a fiber-pigtailed laser diode having 144 mW of optical power. Measurements made using a vector network analyzer show that the attenuator performance can be explained by a classical plasma absorption argument, whereby the microwave signal is attenuated by the optically induced solid-state plasma. Edge-coupled Fabry-Perot aluminum-gallium-arsenidegallium-arsenide AlGaAsGaAs semiconductor LDs, as well as both silicon and gallium-arsenide GaAs CPW-PCSs, were developed for the optoelectronic attenuator. When conventional gain-switching techniques are used, LD peak Output powers greater than 1 W have been demonstrated, and when an optical Q-switching scheme is used, 6 W of peak power has been achieved in tens of picoseconds. jg

Descriptors:

• *OPTICAL PROPERTIES
• *INTEGRATED CIRCUITS
• *MICROWAVES
• *ELECTRIC SWITCHES
• *ATTENUATORS
• DIODES
• Q SWITCHING
• OUTPUT
• CONTROL
• ELECTROOPTICS
• NETWORKS
• PLASMAS(PHYSICS)
• GALLIUM ARSENIDES
• ALUMINUM GALLIUM ARSENIDES
• SEMICONDUCTOR LASERS
• TRANSMISSION LINES
• MICROWAVE EQUIPMENT
• SEMICONDUCTOR DIODES
• LASERS
• OPTICAL WAVEGUIDES
• PEAK POWER
• SIGNALS
• SILICON
• PLANAR STRUCTURES
• VECTOR ANALYSIS
• ATTENUATION
• POWER
• ABSORPTION
• ANALYZERS
• PHOTOCONDUCTIVITY
• MICROWAVE TRANSMISSION

Subject Categories:

• Inorganic Chemistry
• Electrical and Electronic Equipment
• Fluid Mechanics
• Radiofrequency Wave Propagation

Distribution Statement:

APPROVED FOR PUBLIC RELEASE